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991.
对385例急性心肌梗死患者作选择性冠状动脉造影。心电图定位为前壁心梗的相关血管89%是左前降支动脉(LAD),下壁心梗的相关血管76.4%是右冠状动脉(RCA)。阻塞发生于 LAD、RCA及左迥旋支动脉(LCX)近端的分别占67%、58%与78%。近端病变90%以上为重度或完全阻塞。在下壁心梗早期心电图出现心前导联 ST 段下移,是病变广泛的一项指标。  相似文献   
992.
Uptake of the amino acidsl-glycine,l-leucine,dl-methionine, anddl-ornithine by the small bowel of the rat was enhanced during a 4 to 5 day period following hypophysectomy but was subsequently depressed. Synthesis of small-bowel protein was depressed soon after hypophysectomy. These early effects were independent of the reduced food intake by the hypophysectomized animals.  相似文献   
993.
目的 探讨持续性心房颤动 2 4h心室率的变化情况。方法 选持续性 AF患者 79例 ,根据是否合并心力衰竭分为非心力衰竭组与心力衰竭组 ,两组病人均行 2 4h动态心电图检查 ,采用最快心室率、最慢心室率、平均心室率、2 4h总心搏数、2 4h每小时的平均心室率等参数分析 2 4h心室率波动情况。结果 心力衰竭组因使用地高辛控制心室率 ,非心力衰竭组各心室率指标最快、最慢及平均心室率均快于心力衰竭组 ,有显著性差异 ( P<0 .0 5 ,P<0 .0 0 1) ,2 4h总心搏数也多于心力衰竭组 ,有明显统计学意义 ( P<0 .0 0 1)。AF患者 2 4h每小时平均心室率的趋势图表明 :两组病人心室率于凌晨 6:0 0开始上升 ,至上午 8:0 0~ 10 :0 0达高峰 (最快心室率非心力衰竭组为 10 3 bpm ,心力衰竭组为 87bpm ) ,而在夜间 0 :0 0~ 5 :0 0最慢 (非心力衰竭组为 76bpm ,心力衰竭组为 65 bpm ) ,两组病人均有昼快夜慢节律变化 ;心力衰竭组每小时的平均心室率均低于非心力衰竭组。结论 根据本文结果 ,建议临床于心室率高峰前用药 ,旨在有效地控制最快心室率 ,使之维持活动时合适的心室率 ,改善血流动力学变化 ,减轻临床症状  相似文献   
994.
Infusions of large numbers (> 10(8)/kg) of donor leukocytes can induce remissions in patients with chronic myeloid leukemia (CML) who relapse after marrow transplantation. We wanted to determine if substantially lower numbers of donor leukocytes could induce remissions and, if so, whether this would reduce the 90% incidence of graft-versus-host disease (GVHD) associated with this therapy. Twenty-two patients with relapsed CML were studied: 2 in molecular relapse, 6 in cytogenetic relapse, 10 in chronic phase, and 4 in accelerated phase. Each patient received escalating doses of donor leukocytes at 4- to 33-week intervals. Leukocyte doses were calculated as T cells per kilogram of recipient weight. There were 8 dose levels between 1 x 10(5) and 5 x 10(8). Lineage-specific chimerism and residual leukemia detection were assessed using sensitive polymerase chain reaction (PCR) methodologies. Nineteen of the 22 patients achieved remission. Remissions were achieved at the following T-cell doses: 1 x 10(7) (n = 8), 5 x 10(7) (n = 4), 1 x 10(8) (n = 3), and 5 x 10(8) (n = 4). To date, 15 of the 17 evaluable patients have become BCR-ABL negative by PCR. The incidence of GVHD was correlated with the dose of T cells administered. Only 1 of the 8 patients who achieved remission at a T-cell dose of 1 x 10(7)/kg developed GVHD, whereas this complication developed in 8 of the 11 responders who received a T-cell dose of > or = 5 x 10(7)/kg. Three patients died in remission, 1 secondary to marrow aplasia, 1 of respiratory failure and 1 of complications of chronic GVHD. Sixteen patients who were mixed T-cell chimeras before treatment became full donor T-cell chimeras at the time of remission. Donor leukocytes with a T-cell content as low as 1 x 10(7)/kg can result in complete donor chimerism together with a potent graft-versus-leukemia (GVL) effect. The dose of donor leukocytes or T cells used may be important in determining both the GVL response and the incidence of GVHD. In many patients, this potent GVL effect can occur in the absence of clinical GVHD.  相似文献   
995.
Inadequacy of predicted creatinine clearance as guide to chemotherapy   总被引:2,自引:0,他引:2  
Many chemotherapeutic agents are nephrotoxic and/or excreted via the kidney. Thus, careful evaluation of renal function is important since drug dosages are often lowered in patients with impaired renal function. When the creatinine clearance as calculated by the method of Cockcroft and Gault from the patient's age, weight, and serum creatinine was compared to the measured creatinine clearance in the same patients, the correlation coefficient was low (r = 0.40) and the average difference between the predicted and measured creatinine clearance values was 25.3%. Thus, in our patient population, creatinine clearance calculated by the method of Cockcroft and Gault did not correlate well with measured creatinine clearance and thus was not useful as a clinical tool.  相似文献   
996.
997.
998.
We previously have characterized a cluster of genes encoding cathepsin G (CG) and two other CG-like hematopoietic serine proteases, CGL-1 and CGL-2, on human chromosome 14. In this report, we clone and characterize a novel, related murine hematopoietic serine protease gene using human CG (hCG) cDNA as the probe. This murine gene spans approximately 2.5 kb of genomic DNA, is organized into five exons and four introns, and bears a high degree of homology to hCG at both nucleic acid (73%) and deduced amino acid (66%) levels. The predicted cDNA contains an open reading frame of 783 nucleotides that encodes a nascent protein of 261 amino acids. Processing of a putative signal (pre) peptide of 18 residues and an activation (pro) dipeptide would generate a mature enzyme of approximately 27 Kd that has an estimated pI of 12.0. Conserved residues at His44, Asp88, and Ser181 form the characteristic catalytic triad of the serine protease superfamily. The gene is tightly linked to the CTLA-1 locus on murine chromosome 14, where the serine protease genes mCCP1-4 are clustered. Expression of this gene is detected only in the bone marrow and is restricted to a small population of early myeloid cells. These findings are consistent with the identification of the gene encoding murine CG.  相似文献   
999.
1000.
BACKGROUND: Population based colorectal cancer survival among patients diagnosed in 1985-89 was lower in Europe than in the USA (45% v 59% five year relative survival). AIMS: To explain this difference in survival using a new analytic approach for patients diagnosed between 1990 and 1991. SUBJECTS: A total of 2492 European and 11 191 US colorectal adenocarcinoma patients registered by 10 European and nine US cancer registries. METHODS: We obtained clinical information on disease stage, number of lymph nodes examined, and surgical treatment. We analysed three year relative survival, calculating relative excess risks of death (RERs, referent category US patients) adjusted for age, sex, site, surgery, stage, and number of nodes examined, using a new multivariable approach. RESULTS: We found that 85% of European patients and 92% of US patients underwent surgical resection. Three year relative survival was 69% for US patients and 57% for European patients. After adjustment for age, sex, and site, the RER was significantly high in all 10 European populations, ranging from 1.07 (95% confidence interval 0.86-1.32) (Modena, Italy) to 2.22 (1.79-2.76) (Thames, UK). After further adjustment for stage, surgical resection, and number of nodes examined (a determinant of stage), RERs ranged from 0.77 (0.62-0.96) to 1.59 (1.28-1.97). For some European registries the excess risk was small and not statistically significant. CONCLUSIONS: US-Europe survival differences in colorectal cancer are large but seem to be mostly attributable to differences in stage at diagnosis. There are wide variations in diagnostic and surgical practice between Europe and the USA.  相似文献   
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